AllMovie

One of the most famous of all Avengers episodes, this is a loopy send-up of vintage movie serials. It all begins with the mysterious blackout of an early warning radar system. Steed and Emma's investigation leads them to a hospital run by elderly railway men. Upon learning the truth behind this seemingly innocent facade, Emma is overpowered and tied to the railroad tracks while a huge steam train rapidly approaches. Written by Malcolm Hulke, "The Gravediggers" originally aired in England on October 9, 1965; it was subsequently broadcast in America on August 4, 1966.